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The rapid, sensitive and specific detection of SARS-CoV-2 is critical in responding to the current COVID-19 outbreak. In this proof-of-concept study, we explored the potential of targeted mass spectrometry based (MS) proteomics for the detection of SARS-CoV-2 proteins in both research samples and clinical specimens. First, we assessed the limit of detection for several SARS-CoV-2 proteins by parallel reaction monitoring (PRM) MS in infected Vero E6 cells. For tryptic peptides of Nucleocapsid protein, the limit of detection was in the mid-attomole range (9E-13 g). Next, this PRM methodology was applied to the detection of viral proteins in various COVID-19 patient clinical specimens, such as sputum and nasopharyngeal swabs. SARS-CoV-2 proteins were detected in these samples with high sensitivity in all specimens with PCR Ct values

Background Somatic tissue oxygen saturation (SstO2) is associated with systemic hypoperfusion. Kidney dysfunction may lead to increased mortality and morbidity in patients who undergo living donor liver transplantation (LDLT). We investigated the clinical utility of SstO2 during LDLT for identifying postoperative kidney dysfunction. Patients and methods Data from 304 adults undergoing elective LDLT between January 2015 and February 2020 at Seoul St. Mary’s Hospital were retrospectively collected. Thirty-six patients were excluded based on the exclusion criteria. In total, 268 adults were analyzed, and 200 patients were 1:1 propensity score (PS)-matched. Results Patients with early kidney dysfunction had significantly lower intraoperative SstO2 values than those with normal kidney function. Low SstO2 (< 66%) 1 h after graft reperfusion was more highly predictive of early kidney dysfunction than the values measured in other intraoperative phases. A decline in the SstO2 was also related to kidney dysfunction. Conclusions Kidney dysfunction after LDLT is associated with patient morbidity and mortality. Our results may assist in the detection of early kidney dysfunction by providing a basis for analyzing SstO2 in patients undergoing LDLT. A low SstO2 (< 66%), particularly 1 h after graft reperfusion, was significantly associated with early kidney dysfunction after surgery. SstO2 monitoring may facilitate the identification of early kidney dysfunction and enable early management of patients.

Age-related changes in ion channel expression are likely to affect neuronal signaling. Here, we examine how age affects Kv4/Shal and Kv1/Shaker K+ channel protein levels in Drosophila. We show that Kv4/Shal protein levels decline sharply from 3 days to 10 days, then more gradually from 10 to 40 days after eclosion. In contrast, Kv1/Shaker protein exhibits a transient increase at 10 days that then stabilizes and eventually declines at 40 days. We present data that begin to show a relationship between reactive oxygen species (ROS), Kv4/Shal, and locomotor performance. We show that Kv4/Shal levels are negatively affected by ROS, and that over-expression of Catalase or RNAi knock-down of the ROS-generating enzyme, Nicotinamide Adenine Dinucleotide Phosphate (NADPH) Oxidase (NOX), can attenuate the loss of Kv4/Shal protein. Finally, we compare levels of Kv4.2 and Kv4.3 in the hippocampus, olfactory bulb, cerebellum, and motor cortex of mice aged 6 weeks and 1 year. While there was no global decline in Kv4.2/4.3 that parallels what we report in Drosophila, we did find that Kv4.2/4.3 are differentially affected in various brain regions; this survey of changes may help inform mammalian studies that examine neuronal function with age.

Abnormal calcium absorption and iron overload from iron hyperabsorption can contribute to osteoporosis as found in several diseases, including hemochromatosis and thalassemia. Previous studies in thalassemic mice showed the positive effects of the iron uptake suppressor, hepcidin, on calcium transport. However, whether this effect could be replicated in other conditions is not known. Therefore, this study aimed to investigate the effects of hepcidin on iron and calcium uptake ability under physiological, iron uptake stimulation and calcium uptake suppression. To investigate the potential mechanism, effects of hepcidin on the expression of iron and calcium transporter and transport-associated protein in Caco-2 cells were also determined. Our results showed that intestinal cell iron uptake was significantly increased by ascorbic acid together with ferric ammonium citrate (FAC), but this phenomenon was suppressed by hepcidin. Interestingly, hepcidin significantly increased calcium uptake under physiological condition but not under iron uptake stimulation. While hepcidin significantly suppressed the expression of iron transporter, it had no effect on calcium transporter expression. This indicated that hepcidin-induced intestinal cell calcium uptake did not occur through the stimulation of calcium transporter expression. On the other hand, 1,25(OH)2D3 effectively induced intestinal cell calcium uptake, but it did not affect intestinal cell iron uptake or iron transporter expression. The 1,25(OH)2D3-induced intestinal cell calcium uptake was abolished by 12 mM CaCl2; however, hepcidin could not rescue intestinal cell calcium uptake suppression by CaCl2. Taken together, our results showed that hepcidin could effectively and concurrently induce intestinal cell calcium uptake while reducing intestinal cell iron uptake under physiological and iron uptake stimulation conditions, suggesting its therapeutic potential for inactive calcium absorption, particularly in thalassemic patients or patients who did not adequately respond to 1,25(OH)2D3.

Introduction Peripheral artery disease (PAD) is a highly morbid condition in which impaired blood flow to the limbs leads to pain and tissue loss. Previously we identified 670 nm electromagnetic energy (R/NIR) to increase nitric oxide levels in cells and tissue. NO elicits relaxation of smooth muscle (SMC) by stimulating potassium efflux and membrane hyperpolarization. The actions of energy on ion channel activity have yet to be explored. Here we hypothesized R/NIR stimulates vasodilation through activation of potassium channels in SMC. Methods Femoral arteries or facial arteries from C57Bl/6 and Slo1-/- mice were isolated, pressurized to 60 mmHg, pre-constricted with U46619, and irradiated twice with energy R/NIR (10 mW/cm2 for 5 min) with a 10 min dark period between irradiations. Single-channel K+ currents were recorded at room temperature from cell-attached and excised inside-out membrane patches of freshly isolated mouse femoral arterial muscle cells using the patch-clamp technique. Results R/NIR stimulated vasodilation requires functional activation of the large conductance potassium channels. There is a voltage dependent outward current in SMC with light stimulation, which is due to increases in the open state probability of channel opening. R/NIR modulation of channel opening is eliminated pharmacologically (paxilline) and genetically (BKca α subunit knockout). There is no direct action of light to modulate channel activity as excised patches did not increase the open state probability of channel opening. Conclusion R/NIR vasodilation requires indirect activation of the BKca channel.

The first symptoms of schizophrenia (SCHZ) are usually observed during adolescence, a developmental period during which first exposure to psychoactive drugs also occurs. These epidemiological findings point to adolescence as critical for nicotine addiction and SCHZ comorbidity, however it is not clear whether exposure to nicotine during this period has a detrimental impact on the development of SCHZ symptoms since there is a lack of studies that investigate the interactions between these conditions during this period of development. To elucidate the impact of a short course of nicotine exposure across the spectrum of SCHZ-like symptoms, we used a phencyclidine-induced adolescent mice model of SCHZ (2.5mg/Kg, s.c., daily, postnatal day (PN) 38-PN52; 10mg/Kg on PN53), combined with an established model of nicotine minipump infusions (24mg/Kg/day, PN37-44). Behavioral assessment began 4 days after the end of nicotine exposure (PN48) using the following tests: open field to assess the hyperlocomotion phenotype; novel object recognition, a declarative memory task; three-chamber sociability, to verify social interaction and prepulse inhibition, a measure of sensorimotor gating. Phencyclidine exposure evoked deficits in all analyzed behaviors. Nicotine history reduced the magnitude of phencyclidine-evoked hyperlocomotion and impeded the development of locomotor sensitization. It also mitigated the deficient sociability elicited by phencyclidine. In contrast, memory and sensorimotor gating deficits evoked by phencyclidine were neither improved nor worsened by nicotine history. In conclusion, our results show for the first time that nicotine history, restricted to a short period during adolescence, does not worsen SCHZ-like symptoms evoked by a phencyclidine-induced mice model.

ObjectiveAccumulating evidence suggests that amino acids, particularly tryptophan and glutamate, play an important role in the pathology of depression, but prospective epidemiologic data on this issue is scarce. We examined the association between circulating amino acids and the risk of depressive symptoms in a Japanese working population.MethodsParticipants were 841 workers who were free from depressive symptoms and provided blood at baseline and completed 3-yr follow-up survey. 30 varieties of amino acid concentrations in serum were measured using liquid chromatography/mass spectrometry. Depressive symptoms were defined using the Center for Epidemiologic Studies Depression Scale. Logistic regression was used to calculate the odds ratios of depressive symptoms according to serum amino acids with adjustment for lifestyle factors.ResultsA total of 151 (18.0%) workers were newly identified as having depressive symptoms at the follow-up. Baseline tryptophan and glutamate concentrations in serum were not appreciably associated with the risk of depressive symptoms. Risk of depressive symptoms tended to increase with increasing arginine concentrations; the multivariable-adjusted odds ratio for the highest versus lowest tertile of serum arginine was 1.65 (95% confidence interval: 0.96–2.83; P for trend = 0.07). No clear association was found for other amino acids.ConclusionsResults of the present study do not support a significant role of circulating amino acids in the development of depressive symptoms among Japanese.

Salinity is one of the main abiotic stresses limiting crop productivity. In the current study, the transcriptome of wheat leaves in an Iranian salt-tolerant cultivar (Arg) was investigated in response to salinity stress to identify salinity stress-responsive genes and mechanisms. More than 114 million reads were generated from leaf tissues by the Illumina HiSeq 2500 platform. An amount of 81.9% to 85.7% of reads could be mapped to the wheat reference genome for different samples. The data analysis led to the identification of 98819 genes, including 26700 novel transcripts. A total of 4290 differentially expressed genes (DEGs) were recognized, comprising 2346 up-regulated genes and 1944 down-regulated genes. Clustering of the DEGs utilizing Kyoto Encyclopedia of Genes and Genomes (KEGG) indicated that transcripts associated with phenylpropanoid biosynthesis, transporters, transcription factors, hormone signal transduction, glycosyltransferases, exosome, and MAPK signaling might be involved in salt tolerance. The expression patterns of nine DEGs were investigated by quantitative real-time PCR in Arg and Moghan3 as the salt-tolerant and susceptible cultivars, respectively. The obtained results were consistent with changes in transcript abundance found by RNA-sequencing in the tolerant cultivar. The results presented here could be utilized for salt tolerance enhancement in wheat through genetic engineering or molecular breeding.